In some conventional semiconductor production systems, semiconductor devices are produced while a plurality of process ships intended for processing wafers or keeping the wafers on standby therein are coupled to a loader module intended for housing, transferring, and so on of the wafers, and in semiconductor production systems of such a type, additional installation of process ships is possible.
Here, when a process ship is to be additionally installed, the process ship to be additionally installed is coupled to the loader module and the whole system is operated in order to check the operation of the process ship. Further, when the maintenance of the process ship is to be performed, the electric power to the whole system is interrupted to stop the whole system.
However, in the method in which the whole system is operated in order to check the operation of the process ship, it is necessary to prepare all modules and parts and normally connect them, which has posed the problem of a long startup time of the system.
Moreover, in the method in which the whole system is stopped when the maintenance of the process ship is performed, there has been a problem that production efficiency is lowered since other process ships are caused to be in a non-operable state.